ps_search_t *
phone_loop_search_init(cmd_ln_t *config,
acmod_t *acmod,
dict_t *dict)
{
phone_loop_search_t *pls;
/* Allocate and initialize. */
pls = ckd_calloc(1, sizeof(*pls));
ps_search_init(ps_search_base(pls), &phone_loop_search_funcs,
config, acmod, dict, NULL);
phone_loop_search_reinit(ps_search_base(pls), ps_search_dict(pls),
ps_search_dict2pid(pls));
return ps_search_base(pls);
}
ps_search_t *
phone_loop_search_init(cmd_ln_t *config,
acmod_t *acmod,
dict_t *dict)
{
phone_loop_search_t *pls;
/* Allocate and initialize. */
pls = (phone_loop_search_t *)ckd_calloc(1, sizeof(*pls));
ps_search_init(ps_search_base(pls), &phone_loop_search_funcs,
PS_SEARCH_TYPE_PHONE_LOOP, PS_DEFAULT_PL_SEARCH,
config, acmod, dict, NULL);
phone_loop_search_reinit(ps_search_base(pls), ps_search_dict(pls),
ps_search_dict2pid(pls));
return ps_search_base(pls);
}
static void
fwdflat_word_transition(ngram_search_t *ngs, int frame_idx)
{
int32 cf, nf, b, thresh, pip, i, w, newscore;
int32 best_silrc_score = 0, best_silrc_bp = 0; /* FIXME: good defaults? */
bptbl_t *bp;
int32 *rcss;
root_chan_t *rhmm;
int32 *awl;
float32 lwf;
dict_t *dict = ps_search_dict(ngs);
dict2pid_t *d2p = ps_search_dict2pid(ngs);
cf = frame_idx;
nf = cf + 1;
thresh = ngs->best_score + ngs->fwdflatbeam;
pip = ngs->pip;
best_silrc_score = WORST_SCORE;
lwf = ngs->fwdflat_fwdtree_lw_ratio;
/* Search for all words starting within a window of this frame.
* These are the successors for words exiting now. */
get_expand_wordlist(ngs, cf, ngs->max_sf_win);
/* Scan words exited in current frame */
for (b = ngs->bp_table_idx[cf]; b < ngs->bpidx; b++) {
xwdssid_t *rssid;
int32 silscore;
bp = ngs->bp_table + b;
ngs->word_lat_idx[bp->wid] = NO_BP;
if (bp->wid == ps_search_finish_wid(ngs))
continue;
/* DICT2PID location */
/* Get the mapping from right context phone ID to index in the
* right context table and the bscore_stack. */
rcss = ngs->bscore_stack + bp->s_idx;
if (bp->last2_phone == -1)
rssid = NULL;
else
rssid = dict2pid_rssid(d2p, bp->last_phone, bp->last2_phone);
/* Transition to all successor words. */
for (i = 0; ngs->expand_word_list[i] >= 0; i++) {
int32 n_used;
w = ngs->expand_word_list[i];
/* Get the exit score we recorded in save_bwd_ptr(), or
* something approximating it. */
if (rssid)
newscore = rcss[rssid->cimap[dict_first_phone(dict, w)]];
else
newscore = bp->score;
if (newscore == WORST_SCORE)
continue;
/* FIXME: Floating point... */
newscore += lwf
* (ngram_tg_score(ngs->lmset,
dict_basewid(dict, w),
bp->real_wid,
bp->prev_real_wid,
&n_used) >> SENSCR_SHIFT);
newscore += pip;
/* Enter the next word */
if (newscore BETTER_THAN thresh) {
rhmm = (root_chan_t *) ngs->word_chan[w];
if ((hmm_frame(&rhmm->hmm) < cf)
|| (newscore BETTER_THAN hmm_in_score(&rhmm->hmm))) {
hmm_enter(&rhmm->hmm, newscore, b, nf);
/* DICT2PID: This is where mpx ssids get introduced. */
/* Look up the ssid to use when entering this mpx triphone. */
hmm_mpx_ssid(&rhmm->hmm, 0) =
dict2pid_ldiph_lc(d2p, rhmm->ciphone, rhmm->ci2phone,
dict_last_phone(dict, bp->wid));
assert(IS_S3SSID(hmm_mpx_ssid(&rhmm->hmm, 0)));
E_DEBUG(6,("ssid %d(%d,%d) = %d\n",
rhmm->ciphone, dict_last_phone(dict, bp->wid), rhmm->ci2phone,
hmm_mpx_ssid(&rhmm->hmm, 0)));
bitvec_set(ngs->word_active, w);
}
}
}
/* Get the best exit into silence. */
if (rssid)
silscore = rcss[rssid->cimap[ps_search_acmod(ngs)->mdef->sil]];
else
silscore = bp->score;
if (silscore BETTER_THAN best_silrc_score) {
best_silrc_score = silscore;
best_silrc_bp = b;
}
}
/* Transition to <sil> */
newscore = best_silrc_score + ngs->silpen + pip;
if ((newscore BETTER_THAN thresh) && (newscore BETTER_THAN WORST_SCORE)) {
w = ps_search_silence_wid(ngs);
rhmm = (root_chan_t *) ngs->word_chan[w];
if ((hmm_frame(&rhmm->hmm) < cf)
|| (newscore BETTER_THAN hmm_in_score(&rhmm->hmm))) {
hmm_enter(&rhmm->hmm, newscore,
best_silrc_bp, nf);
bitvec_set(ngs->word_active, w);
}
}
/* Transition to noise words */
newscore = best_silrc_score + ngs->fillpen + pip;
if ((newscore BETTER_THAN thresh) && (newscore BETTER_THAN WORST_SCORE)) {
for (w = ps_search_silence_wid(ngs) + 1; w < ps_search_n_words(ngs); w++) {
rhmm = (root_chan_t *) ngs->word_chan[w];
/* Noise words that aren't a single phone will have NULL here. */
if (rhmm == NULL)
continue;
if ((hmm_frame(&rhmm->hmm) < cf)
|| (newscore BETTER_THAN hmm_in_score(&rhmm->hmm))) {
hmm_enter(&rhmm->hmm, newscore,
best_silrc_bp, nf);
bitvec_set(ngs->word_active, w);
}
}
}
/* Reset initial channels of words that have become inactive even after word trans. */
i = ngs->n_active_word[cf & 0x1];
awl = ngs->active_word_list[cf & 0x1];
for (w = *(awl++); i > 0; --i, w = *(awl++)) {
rhmm = (root_chan_t *) ngs->word_chan[w];
if (hmm_frame(&rhmm->hmm) == cf) {
hmm_clear_scores(&rhmm->hmm);
}
}
}
/**
* Build HMM network for one utterance of fwdflat search.
*/
static void
build_fwdflat_chan(ngram_search_t *ngs)
{
int32 i, wid, p;
root_chan_t *rhmm;
chan_t *hmm, *prevhmm;
dict_t *dict;
dict2pid_t *d2p;
dict = ps_search_dict(ngs);
d2p = ps_search_dict2pid(ngs);
/* Build word HMMs for each word in the lattice. */
for (i = 0; ngs->fwdflat_wordlist[i] >= 0; i++) {
wid = ngs->fwdflat_wordlist[i];
/* Single-phone words are permanently allocated */
if (dict_is_single_phone(dict, wid))
continue;
assert(ngs->word_chan[wid] == NULL);
/* Multiplex root HMM for first phone (one root per word, flat
* lexicon). diphone is irrelevant here, for the time being,
* at least. */
rhmm = listelem_malloc(ngs->root_chan_alloc);
rhmm->ci2phone = dict_second_phone(dict, wid);
rhmm->ciphone = dict_first_phone(dict, wid);
rhmm->next = NULL;
hmm_init(ngs->hmmctx, &rhmm->hmm, TRUE,
bin_mdef_pid2ssid(ps_search_acmod(ngs)->mdef, rhmm->ciphone),
bin_mdef_pid2tmatid(ps_search_acmod(ngs)->mdef, rhmm->ciphone));
/* HMMs for word-internal phones */
prevhmm = NULL;
for (p = 1; p < dict_pronlen(dict, wid) - 1; p++) {
hmm = listelem_malloc(ngs->chan_alloc);
hmm->ciphone = dict_pron(dict, wid, p);
hmm->info.rc_id = (p == dict_pronlen(dict, wid) - 1) ? 0 : -1;
hmm->next = NULL;
hmm_init(ngs->hmmctx, &hmm->hmm, FALSE,
dict2pid_internal(d2p,wid,p),
bin_mdef_pid2tmatid(ps_search_acmod(ngs)->mdef, hmm->ciphone));
if (prevhmm)
prevhmm->next = hmm;
else
rhmm->next = hmm;
prevhmm = hmm;
}
/* Right-context phones */
ngram_search_alloc_all_rc(ngs, wid);
/* Link in just allocated right-context phones */
if (prevhmm)
prevhmm->next = ngs->word_chan[wid];
else
rhmm->next = ngs->word_chan[wid];
ngs->word_chan[wid] = (chan_t *) rhmm;
}
}
